Electrical

Question 1

Components of Electrical system (AC and DC)

Answer 1

AC:

• 2 x IDGs
• 1 x APU gen
• 1 x inverter
• 1 x Ram Air Turnine (RAT)
• 1 x AC external power

DC:

• 2 x Nicad Batteries
• 3 x TRUs
• 1 x DC external power

Question 2

AVAIL light on GPU button

Answer 2

AC GPU is connected to the airplane and AC power quality requirements (voltage/amperage/frequency) are satisfied

Question 3

Amber dashes on Electrical synoptic page

Answer 3

output is invalid or out of range

Question 4

Output rating of IDGs and APU Gern

Answer 4

• 40 kVA
• 115 VAC
• 400 Hz
• 3 phase

Question 5

When are IDGs automatically disconnected?

Answer 5

• manual disconnection is not performed, and

- the IDG oil temperature reaches 366°F (185.6°C)

Question 6

Output rating of Ram Air Turning

Answer 6

15 kVA
115 VAC
400 Hz
3- phase

Question 7

Speed required to ensure RAT supplies AC/DC ESS Buses

Answer 7

130 knts

Question 8

How long for RAT deployment

Answer 8

8 secs

*Batts supply backup power to DC ESS and STANDBY AC during rat deployment

Question 9

Output of TRUs

Answer 9

• 300 Amps
• primary source of DC power
• converts 115 VAC —> 28VDC

Question 10

TRUs provide DC power to which busses?

Answer 10

TRU 1 —> DC BUS 1, DC ESS BUS 1, DC GND SVC BUS, HOT BATT BUS 1 and battery #1 charging

TRU 2 —> DC BUS 2, DC ESS BUS 2, HOT BATT BUS 2 and battery #2 charging
TRU ESS —> DC ESS BUS 3

Question 11

Output of Nicad batteries

Answer 11

• 22.8 VDC
• 27 A
• can supply electrical loads for 10 mins without help from GPU

Question 12

Components of electrical power distribution and control

Answer 12

• 4 x Integrated Control Center (ICCs):
  
  • Left Integrated Control Center (LICC)
  • Right Integrated Control Center (RICC)
  • Emergency Integrated Control Center (EICC)
  • Auxiliary Integrated Control Center (AICC)
• 2 x Secondary Power Distribution Assemblies (SPDAs)

Question 13

Electrical Bus locations

Answer 13

LICC - AC BUS 1, AC GND SVC BUS, DC GND SVC BUS, DC BUS 1
RICC - AC BUS 2, DC BUS 2, DC ESS BUS 2
EICC - AC ESS BUS, STBY AC BUS, DC ESS BUS 1, DC ESS BUS 3, HOT BATT BUS 1
AICC - HOT BATT BUS 2, APU START BUS

Question 14

Which buses power the SPDAs

Answer 14

SPDA 1 - DC BUS 1 , DC ESS BUS 1, DC ESS BUS 2, DC GND SVC BUS

SPDA 2 - DC BUS 2, DC ESS BUS 1, DC ESS BUS 2, DC GND SVC BUS

Question 15

Which CBs can be monitored by the flight crew

Answer 15

• Thermal non remote CBs located in the cockpit

- Electronic remote CBs located inside the SPDAs

Question 16

Electrical source priority

Answer 16

– Respective IDG.
– APU generator.
– GPU (on ground without APU).
– Opposite IDG

Question 17

Which components are commanded off by SPDA during load shedding

Answer 17

– Galleys and;

– Right windshield heating.

Question 18

How long can the batteries supply electrical power

Answer 18

10 mins

Question 19

IDG OIL message

Answer 19

• Low Oil Pressure, or

- High Oil Temp

Question 20

Which busses does the RAT power when deployed?

Answer 20

• AC ESS Bus
• AC STBY Bus

Via ESS TR:

• DC Bus 1
• DC Bus 2
• DC Bus 3